<template>
  <div>
    <span>全选:</span>
    <input type="checkbox" v-model="isAll"/>
    <button @click="btn">反选</button>
    <ul>
      <li v-for="(obj, index) in arr" :key="index">     
        <input type="checkbox" v-model="obj.c" :value="obj.name"/>
        <span>{{ obj.name }}</span>
      </li>
    </ul>
  </div>
</template>

<script>
export default {
  data() {
    return {
      arr: [
        {
          name: "猪八戒",
          c: false,
        },
        {
          name: "孙悟空",
          c: false,
        },
        {
          name: "唐僧",
          c: false,
        },
        {
          name: "白龙马",
          c: false,
        },
      ],
    };
  },
  // 计算属性
  computed: {
    isAll: {
      set(val){
        // 全选框选中=>小按钮全选
        this.arr.forEach(obj => obj.c = val)
      },
      get(){
        // 小按钮全选=>       
        return this.arr.every(obj => obj.c)
      }
    }
  },
  methods: {
    btn(){
      //反选
      this.arr.forEach(obj => obj.c = !obj.c)
    }
  }
};
</script>

<style>
</style>